Outdoor

The first time I really remember consciously experiencing air pollution was when I moved to Southern California. My wife and I drove from Tennessee to California, and as we drove through western Arizona and entered the eastern boarder of Southern California, I started to notice a faint layer of brown along the horizon of the saguaro cactus-lined desert. The sun was going down at that time, and so I didn’t get the full effect of descending into the air of the Inland Empire. The following morning, I looked outside, and thought for sure it was going to rain, for there was this thick white-gray particulate matter in the air that prevented me from being able to see more than several blocks. It never did rain. I don’t recall if it was the following day or a few days after that when I realized that this was smog. How shocked I was when the realization hit me!

I still remember one day when the smog lifted a bit, and I was able to see the mountains surrounding the valley we were living in. I had no idea that mountains surrounded us! The smog had been so thick that I couldn’t see that far. We ended up living in that environment for 4 years, and our two oldest children were born there. There were seasonal variations in the smog, and some parts of the year were better than others, but it was a constant reminder that I was leaving in an area that was too populated for its own good.

At times, we would go visit some of the beautiful locations up in the mountains. As we would drive higher and higher into the mountains, all-of-a-sudden, we would reach this magical line where the smog would be below us and the pure air above. You could actually look across and see this brown, level line extending across the horizon. It was really eye-opening to see. We loved to get away from that environment and get into the mountains to go to one of the clear mountain lakes, go hiking in the hills, go walking along a stream, or just enjoy the pure air. Those trips were always so relaxing and rejuvenating.

We had moved to Southern California, so that I could attend medical school, and I learned a couple interesting things about the smog while in school. One of the first classes I took was Anatomy and Physiology. Unlike college, where we dissected cats, here we had human cadavers to dissect to learn about the anatomy of the human body. Our cadaver had been a resident of the Inland Empire for their whole life, and when we got into the chest cavity and saw the lungs for the first time, we found that their lungs had black deposits all throughout the lungs. We questioned our professor as to whether the person had been a smoker, and he told us that, no, that person had just lived in the smog. We were shocked! That much damage just from living in the smog!

One more thing I remember about the smog was in relation to lung and lung health as well. Children who grow up in highly air-polluted areas actually have fewer airways than children who do not. You see, when you grow up and develop, the air tubes that go throughout your lungs branch and become smaller, and then branch and become smaller, and then branch again, and so on. In fact, the typical healthy human lung has 28 orders of branching (i.e. 28 time is branches to a smaller airway until it gets to the air sacs called alveoli where the actual exchange with the blood occurs). In children who grow up in such smoggy environments, that decreases to about 20 or 21 orders! That’s a lot of airway that doesn’t develop just because of air pollution!

Knowing that, we weren’t really excited about raising our children in that busy, congested, and polluted environment, so we moved to somewhere much less affected by outdoor air pollution. However, we still didn’t know about the effects of indoor air pollution.

Indoor

According to the United States Environmental Protection Agency, “In the last several years, a growing body of scientific evidence has indicated that the air within homes and other buildings can be more seriously polluted than the outdoor air in even the largest and most industrialized cities. Other research indicates that people spend approximately 90 percent of their time indoors. Thus, for many people, the risks to health may be greater due to exposure to air pollution indoors than outdoors.”

They go on to say that, “There are many sources of indoor air pollution in any home. These include combustion sources such as oil, gas, kerosene, coal, wood, and tobacco products; building materials and furnishings as diverse as deteriorated, asbestos-containing insulation, wet or damp carpet, and cabinetry or furniture made of certain pressed wood products; products for household cleaning and maintenance, personal care, or hobbies; central heating and cooling systems and humidification devices; and outdoor sources such as radon, pesticides, and outdoor air pollution.”

“The relative importance of any single source depends on how much of a given pollutant it emits and how hazardous those emissions are. In some cases, factors such as how old the source is and whether it is properly maintained are significant. For example, an improperly adjusted gas stove can emit significantly more carbon monoxide than one that is properly adjusted.”

“Some sources, such as building materials, furnishings, and household products like air fresheners, release pollutants more or less continuously. Other sources, related to activities carried out in the home, release pollutants intermittently. These include smoking, the use of unvented or malfunctioning stoves, furnaces, or space heaters, the use of solvents in cleaning and hobby activities, the use of paint strippers in redecorating activities, and the use of cleaning products and pesticides in housekeeping. High pollutant concentrations can remain in the air for long periods after some of these activities.”

“If too little outdoor air enters a home, pollutants can accumulate to levels that can pose health and comfort problems. Unless they are built with special mechanical means of ventilation, homes that are designed and constructed to minimize the amount of outdoor air that can "leak" into and out of the home may have higher pollutant levels than other homes. However, because some weather conditions can drastically reduce the amount of outdoor air that enters a home, pollutants can build up even in homes that are normally considered ‘leaky.’”

You may wonder what health effects may be associated with these air pollutants. The EPA notes that immediate symptoms could include, “irritation of the eyes, nose, and throat, headaches, dizziness, and fatigue.” Treatment for this would be, “simply eliminating the person's exposure to the source of the pollution, if it can be identified.” “Certain immediate effects are similar to those from colds or other viral diseases, so it is often difficult to determine if the symptoms are a result of exposure to indoor air pollution. For this reason, it is important to pay attention to the time and place the symptoms occur. If the symptoms fade or go away when a person is away from the home and return when the person returns, an effort should be made to identify indoor air sources that may be possible causes.”

Okay, so these are potential short-term effects. What about long-term effects? “Other health effects may show up either years after exposure has occurred or only after long or repeated periods of exposure. These effects, which include some respiratory diseases, heart disease, and cancer, can be severely debilitating or fatal. It is prudent to try to improve the indoor air quality in your home even if symptoms are not noticeable.”

Well, that lead to the next logical question: How do I improve the indoor air quality in my home? The suggestions from the EPA are three. First, “eliminate individual sources of pollution or reduce their emissions.” That, of course, depends upon your ability to recognize where the sources are coming from and how to eliminate or reduce them. The next step is an easy one for everyone.

Second, “increase the amount of outdoor air coming indoors.” Simple steps involve opening windows and doors and allowing fresh air from outside to come inside the house. If insects are a problem, place screens on the windows or doors. This will still allow air flow but will prevent the insects from coming inside. If you are in cold environments where opening the doors or windows will drop your indoor temperature drastically to the point of making your freezer a useless appliance, then consider checking with your local air-conditioning/heating service to see if your house model brings in outdoor air and removes indoor air, and if there are models that do that more effectively.

Third, buy an air cleaner. There are various shapes and sizes and expenses related to air cleaners. Be a smart consumer and read up on each one if you have a chance. Typically an air cleaner has two main functions to look at. The first is its “percentage efficiency rating.” This measures how much of the pollutant it removes at any given time. The second is its capacity, usually stated in cubic feet per minute. If you have an air cleaner that has a high efficiency rating, but a very low capacity, you won’t get much air cleaning from it. Also, if you have one that has a low efficiency rating but a high capacity, you might be in the same situation. You are really looking for an air cleaner with a high efficiency rating with a larger capacity. That, of course, means more money!

This goes for your vehicle as well. Those who tend (as I did) to drive with the vent on recirculate and the windows closed are doing themselves a disfavor. Open the windows at least a bit, or turn the vent on fresh rather than recirculate. That should help keep pollutants from building up in that small, entrapped environment.

What is my suggestion for the home? Open the windows and doors (at least for short intervals even in cold environments) and increase the exchange with outdoor air. If you are in a smoggy environment like I lived in, move! Get out into nature and breath the healthy, clean air. There is a reason you feel better when you get out doors in nature. We’ll look at that next.

Epidemiological studies consistently point to a direct link between urban air pollution—especially particulate pollution created by combustion powered vehicles and power generation plants—and cardiovascular and pulmonary diseases. Long-term exposure to particulate pollution—tiny particles smaller than 10 microns (a human hair is 70 microns wide)—is known to increase illness and death rates from lung cancer, chronic obstructive pulmonary disease and emphysema. Additionally, exposure to other airborne pollutants, including sulfur dioxide (SO2), nitrogen dioxide (NO2) and ozone (O3), is associated with development of asthma, bronchitis, and respiratory infections.

European researchers investigated the risks of long-term exposure to traffic pollution in a study examining 5000 volunteers selected from the ongoing Netherlands Cohort study on Diet and Cancer (NLCS). They discovered that people living near major roads (and therefore exposed to higher levels of traffic-related air pollution) were more likely to die from cardiopulmonary disease or lung cancer than their rural peers, leading the authors to conclude that 'long-term exposure to traffic-related air pollution may shorten life expectancy.

In addition to causing lung damage, air pollution is now also recognized as a threat to cardiovascular health. Reporting in the March 6, 2002 Journal of the American Medical Association (JAMA), researchers examined long-term health data on 500,000 individuals to compare increases in air pollution levels with incidence of death. They discovered that when air pollution levels suddenly increased, in addition to expected increases in deaths from asthma, pneumonia, and emphysema, there was an unexpected increase in the number of deaths related to heart attacks and stroke. Most surprising was the finding that when air pollution levels rose, so did deaths from all causes, not just those related to the heart and lungs.

Christopher Somers, James Quinn, and colleagues published an earlier study that found that gulls living near a steel mill on Lake Ontario suffered from genetic mutations. In a current study the researchers raised two groups of mice— the first a half-mile downwind of a steel mill on Lake Ontario, and the second about 20 miles away. The mice breathing the polluted air had twice as many mutations in their DNA as the mice breathing fresh country air.